1. Field of the Invention
This invention relates to apparatus for use in carrying out immunological analysis, such as immunological analysis by double and radial immunodiffusion methods in an agar gel layer or other diffusion medium.
2. Description of the Prior Art
Both radial and double immunodiffusion analysis methods depend on two dimensional diffusion through a diffusion medium.
In radial immunodiffusion analysis, a fluid which, for example, contains an antigen is introduced at a particular location into the diffusion medium (for example, an agar gel layer) in which a specific antiserum is incorporated. A precipitate halo is produced as the antigen diffuses into the agar gel and reacts with the antiserum, the final area of the halo being a measure of the concentration of the initial antigen fluid.
Double immunodiffusion analysis is used to compare the reactions of, for example, two different antigen solutions with the same antiserum solution, all three solutions being introduced at respective locations in an agar gel layer and being allowed to diffuse towards each other.
Both the radial and double immunodiffusion analysis methods have been previously carried out by forming the diffusion medium layer in a Petri dish and then introducing the test solutions into depressions of predetermined sizes and spacings made in the medium. To reduce external influences, a cover can be placed on top of the diffusion layer. This technique for radial and double immunodiffusion analysis has several disadvantages including the need to select for each analysis a particular depression size and spacing, the formation of a diffusion layer meniscus which, owing to more rapid drying in the region of the meniscus, tends to attract the diffusing solutions, and a generally poor sensitivity. Further, diffusion is usually slow owing to the almost total enclosure of the diffusion medium which inhibits evaporation therefrom.
It is an object of the invention to provide improved apparatus for carrying out radial and double immunodiffusion analysis.